you didn't try to hang that on your other body part, like them shaolin monks did you?
Actually I did do dit bu Sam in my early years. It makes for some powerful core strength and flexibility.
Make sure to use silk to tie those weights. And breath slowly or you'll be hurt.
More practical were the "human resistance" exercises. But you need to get beyond the sime pushing against erect postures (standing or seiza)
The upper torso needs to be developed as if there were a "springiness" in the spine.
The pelvic girdle is the base, the thoracic and lumbR vertebrae are the spring. If pushed in any direction, the base remains (single weighted as much as possible) and the back muscles literally spring backward (suck-in opponent) and then back at the opponent (spit-out).
We used to do this starting with 1 dimensions (depth) and then all 3 dimensions. Finally, in push hands, the receiver only defends while the attacker is mobile, trying to push him at any and all angles. The defender ultimTely has to change stances a bit but the less he changes stance, the more he learns to use this flexible torso to guard his center.